Tensioning device for shuttles



y 1935- J. B PLEVYAK 2,002,866

TENSIONING DEVICE FOR SHUTTLES Original Filed Dec 2. 1931 [0 amulet Patented May 28, 1935 UNITED STATES PATENT OFFICE Application December 2, 1931, Serial No. 578,598 Renewed January 5, 1935 Claims.

My invention relates to tensioning devices for weavers shuttles.

In the weaving of cloth it is important that the weft, as it is led out from the shuttle, should be held with an even tension in order to produce a smooth weave. This is doubly true of cloth formed of very fine silk threads or strands. In many instances it is desired that sill: cloth of this character should have a glossy appearance; but it is apparent that ii the weft has irregular tension imparted to it, during the weaving process, the threads or strands, as they extend across the cloth from selvedge to selvedge, will be taut at some places and comparatively loose at other places. The taut parts of the thread will he comparatively straight, while the loose parts will be inclined to be wavy. These wavy sections of the threads or strands will not give an even reflection of the rays of light, such as is necessary to present the glossy appearance desired, but will, on the contrary, give a diflused reflection which will tend to impart to the surface of the cloth at these places the appearance of a dull finish instead of a glossy finish.

The object of the present invention is to provide tensioning means which will import to the weft threads or strands a comparatively even tension throughout the entire thrust of the shuttle, so as to produce a cloth having the maximum evenness and smoothness of surface.

The present invention relates to that class of shuttles having a tortuous-course tension, which employs a tensionlng arm having a plurallty of loops, while the horizontal recess in the iorward end of the shuttle where the tensioning device is mounted is provided with a plurality of rigidly-mounted bars. with the thread passing alternately from one of said loops over a bar and back through another loop and from there over another bar, etc., and finally out through an eye in the wall of the shuttle and on to the cloth being woven in the loom. In tensioning devices of this character, the tension arm is very commonly controlled by a rubber band or an elongated coil spring. The present invention substitutes for the rubber band a torsion spring of helical construction and having its coil of comparatively large diameter.

This substitution of the large-coiled torsion spring, and the method of constructing and mounting and holding it in adjusted positions is the only diflerence between the present invention and the ordinary tortuous-course tensioning shuttle.

From the nature of the service which they have (01. Bil-21!) to render, shuttles, must of necessity be comparatively small, so that the tensioning devices which they carry have to be limited to a small space. They are usually located in the forward end of the shuttle in a recess which extends hori- 5 zontally through the shuttle from one side to the other thereof; and this is the kind of a recess which my shuttle employs. It is in this recess and near one side of the shuttle that the rubber band above referred to is usually located.

One difficulty about the ordinary springs used is that when they have been elongated only a comparatively short distance, they rapidly besome much more resistant to yielding than they were at the beginning of the movement, so that they put a very much stronger tension on the thread during a part of the thrust of the shuttle than they do at other parts. In other words, the spring does not have sufllcient range in its yielding mewement to keep an even tension on the thread, but on the contrary approaches rigidity too quickly. The present arrangement overcomes that disadvantage, and gives an even tension on the thread throughout a. comparatively wide range of movement of the tensioning arm, which results in the production of cloth of very smooth texture and with a glossy sheen.

Again; a rubber tension band soon wears out, and not infrequently breaks and falls out 01' the shuttle unobserved. Sometimes when it falls out it is woven into the cloth, thus making a rough and imperfect place in the weave. In fact, a rubber tension band weans out approximately every two weeks, and so must be replaced with a new band about that often.

My steel spring tension will last and do perfect work as long as the shuttle lasts, so that it will not have to be changed or replaced with a new one. It will not weaken or break, but will give an even, constant tension which greatly helps in the production of a perfect cloth.

A further object in view is to provide a. device which will not only have a wide range of movement, but which can also be adjusted to give the desired tension to the threads operated on, according as to whether much or little tension is desired.

Still another object is to provide a device of the character described having durable and compact construction which will not be liable to get out of order; and which can be easily ap plied to the ordinary shuttles such as I have described above.

Minor objects will appear in the subjoined description.

A leading feature of the device consists of a tensioning spring (which is a torsion spring) mounted on a rotatable member adapted to regulate the tension of the spring, and having means for holding said rotatable member in adjusted positions.

The invention consists in certain novel features of construction and arrangement of parts, as will be hereinafter described. and claimed, reference being had to the accompanying drawing, in which;-

Fig. 1 is a side elevation of the device showing the parts removed from the shuttle, but in their operative relation to each other.

Fig. 2 shows in full lines a side elevation of the upper screw the ring screw) illustrated in Fig. 1; and in dotted lines certain other parts located adjacent thereto.

Fig. 3 ls a top plan view of the spring adjuster.

Fig. 4 is a sectional side elevation thereof.

Fig. 5 is a top plan view of the tensioning spring.

Fig. 6 is a side elevation thereof.

Fig. 7 is a bottom plan view of Fig. 6; and,

Fig. 8 is a fragmentary view on a reduced scale, of the forward end of a shuttle, showing the relative position of my device therein.

Referring further to the drawing, the numeral I indicates the ring screw having its upper portion externally threaded, and its lower portion id of a reduced size. This lower reduced portion carries the ordinary tension-arm ring in the usual way, the same being of a diameter to be snugly received thereupon. This ring per se forms no part of my invention.

The ring-screw I, by means of its threaded upper portion, is anchored in the upper wall 2 of the shuttle (Fig. 8), and extends down into the horizontal recess 3. The tensioning device 4 is rotatably mounted in the lower wall 5 of the shuttle in alinement with the ring screw. This tensioning device has a fiat head 4a provided at its centre with a socket 5a, and on its periphcry with a vertical notch or slot 5, and at its lower end it has a diametrical slot 1 for the reception of a screw-driver for turning it.

The lower end of the section la of .the ringscrew is rounded, and fits the socket 5a. of the tensioning device, as clearly shown in Fig. 2.

The spring 8 terminates at its upper end in a hook 9 adapted to engage a cooperating hook of the ring, as illustrated in dotted lines in Fig. 2. The lower coil of the spring terminates in a central ring H! of a size to snugly receive the '1 shank of the tensioning device 4; and this coil is also provided with a loop H between the central ring Ill and the periphery of the spring, which loop is adapted to be received into the slot 6 of the tensioning device, when the parts are assembled in operative relation to each other, as illustrated in Fig. 1.

A set screw I2 is passed in from the front side of the lower wall portion 5 of the shuttle (see Fig. 8) and engages the shank 4 of the adjusting device to hold the same in its adjusted positions.

A washer i3 (Fig. 1) is received onto the shank 4 of the adjusting member underneath the spring 8. When the parts are in their operative posi tion, this washer rests on the bottom of the horizontal recess 3 of the shuttle, as indicated in Fig. 8.

. The ring l4 used with my device is of ordinary construction, and terminates in the usual hook I5 which is adapted to engage the hook 9 at the upper termination of the spring 8.

In operation, the weft thread passes through the tensioning arm (which is partially shown in Fig. 2 extending to the left from the upper end of the portion l4) and the thread, when under normal weaving tension, actuates this arm against the tension of the spring 8 which in turn reacts to take up slack in the thread whenever slack occurs; and thus the device imparts a uniform tension to the thread.

When the parts are to be assembled, as illustrated in Figs. 1, 2, and 8, the washer I3 is first placed in position, as shown in Fig. 8, and then the spring is placed on the washer. Next, the shank of the adjusting member 4 is passed down inside the spring through the ring In and the washer l3, and on down through a suitable bore in the lower wall 5 of the shuttle. This will bring the underside of the head in. of the adjusting member into flat engagement with the ring H] at the termination of the lower side of the spring 8 when the tensioning device has been rotated into position to permit the loop II to extend up into the notch B. In this way the ring II) in the lower coil of the spring will be held between the head 4a of the tensioning member and the washer i3. Next, the ring-screw is passed down through the upper wall 2 of the shuttle, and through the ring M, and on into the socket 5a, of the tensioning member, and is screwed down sufficiently into said socket to hold the ring In firmly compressed between the head 4a and the washer 13. This will always hold the spring 8 reliably in position.

Of course, the washer 13 could be dispensed with, but it serves a good purpose in that it forms a wear-plate between the lower coil of the spring 8 and the wood of the shuttle.

With the parts assembled as described above, it is only necessary to rotate the adjusting member 4 in order to vary the tension of the spring 8.

In operation it will be seen that when the tensioning member 4 is suitably rotated to give the desired tension to the spring 8, a suitable turn of the set screw l2 will lock the tensioning member in the position it hasbeen caused to assume.

If the ring-screw l is screwed down very tightly into the socket 5a, it will hold the adjusting member 4 against rotation without the aid of the set-screw l2, so that said screw is not absolutely necessary to my construction.

The head of the ring-screw I may be easily reached by a screw driver from the upper side of the shuttle; and the diametrical slot 7 at the lower end of the shank 4 of the rotatable tensioning device may be easily reached from the under side of the shuttle.

' From the foregoing, it will be seen that if at any time it becomes necessary to substitute one spring for another of difierent strength, the change can be made with ease and facility, since the ring-screw acts like a key which holds all the other parts in operative relation to each other.

From Fig. 2 it will be seen that my torsion spring 8 engages and operates the hook i5 of the ring i 4, thus taking the place of the rubber cord ordinarily used for that purpose.

The thread passes from the bobbin through an eyelet 6 at the rear end of the recess 3 of the shuttle to the tensioning devices, and from thence passes out through an eyelet 11 in the forward part of the shuttle; or it may be passed out through other eyelets (not shown) in the side of the shuttle.

The dotted lines I8 in Fig. 8 of the drawing simply indicates the other side of the horizontal recess 3 of the shuttle.

From the foregoing, it is believed that the construction and operation of my device will be fully understood.

What I claim as new and desire to protect by Letters Patent is:-

i. In a device of the character described, a tension arm, a torsion spring for controlling said arm; a rotatable tensioning member on which said spring is mounted, said member having means for engaging and holding the lower coil of the spring to rotate the same therewith, the shuttle having a seat therein for the reception of said tensioning member; a ring-screw adjustable toward and from the rotatable tensioning member, and serving the double purpose oi. carrying the ring of the tension arm and of pressing the rotatable tensioning member to hold the same in operative position in its seat; and means for locking the rotatable member in adjusted positions.

2. In a device of the character described, a tension arm, a torsion spring for controlling said arm; a rotatable tensioning member comprising a shank portion and a head portion, the shuttle having a recess for the reception of said shank, and said head portion being arranged for engaging and holding the lower coil of the spring to rotate therewith; a ring screw in alinement with the shank of the tensioning member and adjustable toward and from the head of said member to adapt said screw to press said head to hold said shank in its recess in the shuttle, and also, when desired, to lock said tension member in adjusted positions on the shuttle.

3. In a device of the character described, a torsion spring for controlling the tension arm of the shuttle, said spring terminating at its lower end in a central ring of reduced diameter and having an upwardly extending loop between said central ring and the periphery of the coil; a rotatable tensioning member having a shank adapted to be snugly received into said central ring and having a circular head adapted to rest upon said ring when the shank is passed down into the same, said head having a peripheral notch adapted to receive said loop of the lower coil of the spring, and having at its centre a circular socket; a ring-screw above the tensioning member in alinement therewith and having a reduced shank portion adapted to carry the ring of the tension arm, said shank portion being rounded at its lower end to fit said circular socket of the tensioning member and to be received thereinto to hold said tensioning member in operative position on the shuttle; and means for holding the tensioning member in adjusted positions.

4. In a device of the character described, a tension arm, a torsion spring for controlling said arm; a rotatable tensioning member mounted in a recess in the shuttle, and on which rotatable member said torsion spring is mounted; a washer on the tensioning member underneath the spring; a ring-screw adjustable toward and from the rotatable tensioning member, and arranged for carrying the ring of the tension arm and also for pressing the tensioning member to hold the same in its recess in the shuttle, and when desired, for looking it in adjusted positions; and means independent of said ring-screw for additionally locking said rotatable tensioning member in adjusted positions; whereby said member may be doubly locked in any desired position of adjustment. 7 i

5. In a device of the character described, a torsion spring 'for controlling the tension arm of the shuttle; a rotatable tensioning member on which said spring is mounted; a washer on the tensioning member underneath the spring; a ring-screw for carrying the ring of the tension arm and for holding the tensioning member in operative position; and a set screw for engaging the tensioning member to hold the same in adjusted positions; said torsion spring terminating at its upper end in a hook adapted to engage the ring of the tension arm of the shuttle to control the same; and at its lower end in a central ring of reduced diameter, and having an upwardly extending loop between said central ring and the periphery of the coil; said rotatable tensioning member having a shank adapted to be snugly received into said central ring, and having a circular head adapted to rest on said ring when the shank is passed down into the same, said head having a peripheral notch adapted to receive said loop of the lower coil of the spring and having at centre a circular socket; said ring-screw being located above the tensioning member in alinement therewith, and having a reduced shank portion adapted to carry the ring of the tension arm, said shank portion being rounded on its extreme lower end to fit into said circular socket of the tensioning member to hold said member in operative position on the shuttle.

6. In a device of the character described, a torsion spring for controlling the tension arm of the shuttle; a rotatable tensioning member comprising a shank and a flat head surmounting the same, said spring being formed in coils of larger diameter than said head whereby the head can be received inside of said coils, said spring terminating at its lower end in a reduced central ring of a size to receive the shank of said tensioning member, said tensioning member being arranged to have its head received inside the coils of said spring with its shank extending through said central ring and anchored in the wall of the shuttle with said reduced ring held between said fiat head and said Wall, whereby the torsion spring is held against rocking on the shuttle; and a set screw for engaging said shank to hold the same in adjusted positions.

'7. In a device of the character described, a torsion spring for controlling the tension arm of the shuttle; a rotatable tensioning member comprising a shank and a flat head surmounting the same, said spring being formed in coils of larger diameter than said head whereby the head can be received inside of said coils, said spring terminating at its lower end in a reduced central ring of a size to receive the shank of said tensioning member, said tensioning member being arranged to have its head received inside the coils of said spring with its shank extending through said central ring and anchored in the wall of the shuttle with said reduced ring held between said flat head and said wall, whereby the torsion spring is held against rocking on the shuttle; a ring screw for carrying the tension arm of the shuttle, and for pressing the head of the rotatable tensioning device to hold the shank thereof anchored in the shuttle; and a set screw for engaging said shank to hold the same in adjusted positions.

8. In a device of the character described, a tension arm, a torsion spring for controlling said arm; a rotatable tensioning member on which said spring is mounted, said member having means for engaging and holding the lower coil of the spring to rotate the same therewith; and an adjustable ring-screw for carrying the ring of the tension arm, said rotatable tensioning member being in the path of movement of said screw, whereby said screw is adapted to engage and lock said tensioning member in adjusted positions.

9. In a device of the character described, a tension arm, a torsion spring for controlling said arm; a rotatable tensioning member mounted on the shuttle, and having an ample head in engagement with the shuttle and on which head said spring is mounted, said head having means for engaging and holding the lower coil of the spring to rotate the same therewith; and an adjustable ring-screw for engaging and holding the ring of the tension arm, said screw being disposed in alinement with the axis of said rotatable tensioning member with the head of said member provided with a central socket in the path of said screw, whereby said screw is adapted to enter said socket and to force said head into binding engagement with the shuttle, whereby to lock the rotatable tensioning member in adjusted positions on the shuttle.

10. The combination with a. shuttle having a recess between its upper and lower sides for the reception of a tensioning device, said device comprising a tension arm; a torsion spring for controlling said arm; and a rotatable tensioning member for said spring, said member having a head and a shank portion and being seated in the lower side of the shuttle with its lower end exposed on the bottom of the shuttle to be engaged for operation, said torsion spring being mounted on said tensioning member to be rotated thereby; a ring-screw for carrying the ring of the tension arm and for pressing the head of the tensioning member to hold the same in its recess in the shuttle, said ring-screw being mounted in the upper side of the shuttle in alinement with the axis of the aforesaid tensioning member and having its head exposed to be engaged for operation from the upper, outer side of the shuttle, said ring-screw being arranged for adjustable movement into engagement with the head of the rotatable tensioning member, whereby to lock the same in adjusted positions; and additional means independent of the ringscrew for engaging the shank of the rotatable tensioning member to lock the same in adjusted positions on the shuttle.

JOSEPH B. PLEVYAK. 

